Hydrogen suffocation

Vapor Density (VD) — the mass per unit volume of a given vapor/gas relative to that of air. Thus, acetaldehyde with a vapor density of 1.5 is heavier than air and will accumulate in low spots, while acetylene with a vapor density of 0.9 is lighter than air and will rise and disperse. Heavy vapors present a particular hazard because of the way they accumulate if toxic they may poison workers if nontoxic they may displace air and cause suffocation by oxygen deficiency if flammable, once presented with an ignition source, they represent a fire or explosion hazard. Gases heavier than air include carbon dioxide, chlorine, hydrogen sulfide, and sulfur dioxide. 

Colorless gas that forms heavy clouds in moist air. It has a sharp, irritating and suffocating odor similar to hydrogen chloride. This material is hazardous through inhalation and produces local skin/eye impacts. 

An outbreak of acute intoxication attributed to hydrogen selenide in India in 1994 caused intense cough, suffocation, burning and tearing of the eyes, tachycardia, and severe bronchospasm in 31 patients. Improvement occurred in most after 5 days, but some followup cases showed restrictive and obstructive changes on pulmonary function tests 18 months later. ... 

Sulfuryl Dioxide, SOa(Nj)a, mw 148.11, N 56.7%, col liq first prepd in 1922 by Curtius Schmidt (Ref 2) by the interaction of sulfuryl chloride and finely divided, si moist Na azide SOaCl + 2NaNs - SOa (N3)a + 2NaCl. It explodes violently when heated and often spontaneously at RT. Sax (Ref 9) does not list this compd but it has a suffocating odor and the pronounced physiological effects of hydrogen azide (qv)... 

The chloride is a red, mobile liquid, with a suffocating odour. It has a density of 1-5085 at 15° C., and boils at 73-5° C. It fumes in moist air and is decomposed by water or alkalis, forming carbonic and hydrochloric acids or their salts and hydrogen sulphide. 

The effect of hydrogen cyanide is based on the fact that it paralyzes the respiration of every individual cell in the body. Oxygen can no longer be transported from the blood through the cell walls into the cells.413 As the vital cell functions are thereby starved of oxygen, the animal or human being suffocates. 

Titanium tetrachloride is a colourless transparent liquid (the boiling point is 136 °C) it is easily decomposed with water forming hydrogen chloride and titanium dioxide. It joins the moisture in air to form white suffocating fumes, which are drops of hydrochloric acid. 

Suffocation and breathing atmospheres Each of the foregoing hazards is discussed in the following sections. Table 1 provides certain specific properties of hydrogen useful in examining the hazards discussed in the following sections (1). 

Suffocation. A most unlikely hazard would be personnel exposure to a hydrogen atmosphere sufficient to cause suffocation (a fire would be apt to occur first). However, it must be borne in mind that hydrogen is as dangerous as the inert gases in dilution of a breathing atmosphere. 

Today we have sophisticated lab equipment to help us analyze the products of reactions. In the past, when such equipment was not available, chemists sometimes jeopardized their safety and health to determine the products of the reactions they studied. Sir Humphry Davy (1778-1829), a contributor to many areas of chemistry, thought nothing of inhaling the gaseous products of the chemical reactions that he carried out. He tried to breathe pure C02, then known as fixed air. He nearly suffocated himself by breathing hydrogen. In 1800, Davy inhaled dinitrogen monoxide, N20, otherwise known as nitrous oxide, and discovered its anaesthetic properties. What is nitrous oxide used for today ... 

Hydrogen chloride is a colorless, nonflammable gas with a pungent, suffocating odor (ACGIH 1991). It is very hygroscopic and produces fumes in moist air. The chemical and physical properties of hydrogen chloride are summarized in Table 5-1. 

However, it can be shown that the victims in the airtight chamber would probably have suffocated after only one hour and without any poison gas,134 so that even under these conditions the victims complete absorption of the hydrogen cyanide would have failed due to the slow rate of evaporation of hydrogen cyanide from the Zyklon B carrier material. Thus, this theory not only contradicts the eyewitness statements with respect to quantities of Zyklon B and speed of execution, but is also technically utterly nonsensical, since if the victims had been killed by suffocation there would have been no need to expend the costly Zyklon B, which was in short enough supply even without being wasted. 

Properties Colorless, fuming liquid. Suffocating odor. Sp. gr. 1.5. M. P. —70°. B. P, 57.6°. Decomposes with the moisture of the air, forming a dispersion of silicic acid and hydrogen chloride. 

Properties Colorless, exceedingly mobile, fuming liquid suffocating odor. Corrosive to most metals when water is present in the absence of water it has practically no action on iron, steel, or the common metals and alloys, and can be stored and handled in metal equipment without danger. D 1.483 (20C), bulk d 12.4 lb/gal, fp -70C, bp 57.6C, refr index 1.412 (20C). Miscible with carbon tetrachloride, tin tetrachloride, titanium tetrachloride, and sulfur mono- and dichlorides decomposed by water and alcohol with evolution of hydrogen chloride. Noncombustible. 

Properties Colorless gas suffocating odor similar to hydrogen chloride. Fumes strongly in air, d 3.57 (gas, air = 1) (15C), fp -90C, bp -86C. Absorbed readily in large quantities by water with decomposition soluble in absolute alcohol. Noncombustible. 

Finally, the disposal and destruction of compounds containing polyvinyl chloride may create environmental problems. Burning such products, for example, releases hydrogen chloride gas, a suffocating and toxic gas, into the atmosphere. Enough concern about the health and environmental hazards has arisen that some governmental bodies in Europe have placed limitations on the uses to which PVC products can be put. 

---